[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 080559
SWODY1
SPC AC 080558

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT SAT APR 08 2006

VALID 081200Z - 091200Z

...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS THE EASTERN GULF
STATES INTO THE SOUTHERN/MID ATLANTIC COAST....

SOUTHERN STREAM SHORT WAVE TROUGH HAS FINALLY BECOME MORE
PROGRESSIVE...AND IS NOW DIGGING THROUGH THE LOWER MISSISSIPPI
VALLEY...MORE OR LESS IN PHASE WITH A VIGOROUS NORTHERN BRANCH
TROUGH DIGGING INTO THE LOWER GREAT LAKES/ST. LAWRENCE VALLEY. 
MODELS SUGGEST NORTHERN SYSTEM WILL RAPIDLY PIVOT THROUGH NORTHERN
NEW ENGLAND AND THE CANADIAN MARITIMES DURING THIS FORECAST PERIOD. 
SOUTHERN IMPULSE IS PROGGED TO BE A BIT SLOWER...BUT APPEARS LIKELY
TO GRADUALLY TAKE ON MORE OF A NEUTRAL TILT AS IT APPROACHES THE
MID/SOUTH ATLANTIC COAST BY 12Z SUNDAY.

SURFACE COLD INTRUSIONS ASSOCIATED WITH BOTH FEATURES WILL
EVENTUALLY SURGE THROUGH THE LEE OF THE SOUTHERN APPALACHIANS... AND
THROUGH THE REMAINDER OF THE CENTRAL/EASTERN GULF STATES. 
HOWEVER...THIS GENERALLY WILL NOT OCCUR UNTIL LATER TODAY/TONIGHT.
PRE-FRONTAL ENVIRONMENT IS BECOMING INCREASINGLY MOIST ACROSS THE
EASTERN GULF STATES...AND SIMILAR MOISTENING IS POSSIBLE OVER SOUTH
ATLANTIC COASTAL AREAS AS SURFACE RIDGING FINALLY WEAKENS/RETREATS
TO THE EAST.  SURFACE DEW POINTS AT OR ABOVE 60F MAY OVERSRPREAD
MUCH OF THE SOUTHEAST BY MIDDAY.

COOLING/DRYING IN WAKE OF COLD FRONTS...BENEATH BROADLY ANTICYCLONIC
UPPER FLOW DEVELOPING INTO THE CENTRAL/EASTERN STATES SHOULD
PRECLUDE CONVECTIVE POTENTIAL MOST OTHER AREAS EAST OF THE ROCKIES. 


ACROSS THE WEST...MAIN SHORT WAVE IMPULSE WITHIN BROADER SCALE
TROUGH WILL REMAIN WEST OF THE PACIFIC COAST THROUGH THIS PERIOD. 
BUT...WEAKER IMPULSE ALREADY LIFTING OUT OF TROUGH INTO THE NORTHERN
INTERMOUNTAIN REGION WILL CONTINUE THROUGH THE NORTHERN ROCKIES BY
LATE TONIGHT.

...SOUTHEAST...
MODERATELY STRONG AND SHEARED FLOW REGIME WILL DEVELOP ACROSS MUCH
OF THE REMAINDER OF THE EASTERN GULF/SOUTH ATLANTIC COAST STATES
TODAY. PRIMARY UNCERTAINTY CONCERNING EXTENT OF SEVERE THREAT
INVOLVES INFLUENCE OF CONVECTIVE SYSTEM EXPECTED TO BE ONGOING FROM
THE LEE OF THE SOUTHERN APPALACHIANS THROUGH PARTS OF SOUTHERN
ALABAMA/MISSISSIPPI AT 12Z.  LOWER LEVELS IN THE LEE OF THE
APPALACHIANS MAY STILL BE TOO DRY EARLY IN THE DAY TO SUPPORT
CONTINUING SEVERE THREAT ACROSS THE SOUTH ATLANTIC COAST STATES...
AND CLOUD COVER WITH DISSIPATING CONVECTION COULD IMPEDE SURFACE
HEATING.

BEST MOIST INFLOW INTO CONVECTION IS EXPECTED ACROSS NORTHERN
FLORIDA INTO SOUTHERN GEORGIA...WHERE LINE OF STRONG/SEVERE STORMS
...PRIMARILY WITH HAIL/DAMAGING WINDS...APPEARS POSSIBLE THIS
MORNING INTO EARLY AFTERNOON. 

OTHERWISE...AIR MASS MAY BECOME SUFFICIENTLY UNSTABLE IN WAKE OF
EARLY CONVECTION FOR SCATTERED SEVERE STORMS AHEAD OF COLD FRONT
ACROSS CENTRAL/SOUTHEAST ALABAMA.  STORMS SHOULD FORM AS MID-LEVEL
THERMAL TROUGH AXIS OVERSPREADS ALABAMA DURING THE AFTERNOON
HOURS...AND ACTIVITY COULD SPREAD BACK INTO SOUTHERN GEORGIA BEFORE
WEAKENING.

FARTHER EAST...THOUGH CAPE MAY NOT BECOME PARTICULARLY
STRONG...FORCING AHEAD OF SOUTHERN BRANCH TROUGH COULD BECOME
SUPPORTIVE OF A NEW LINE OF STORMS BY LATE AFTERNOON ACROSS PARTS OF
THE EASTERN CAROLINAS/SOUTHEAST VIRGINIA.  SHEAR WILL BE MORE THAN
SUFFICIENT FOR UPDRAFT ROTATION...BUT PRIMARY SEVERE THREAT SEEMS
LIKELY TO BE DAMAGING WINDS AND HAIL IN 40 TO 50+ KT SOUTHWESTERLY
MEAN FLOW.

..KERR/GUYER.. 04/08/2006